A kit for determining an analyte, preferably an illicit drug, in a sample comprises: (a) a sampling device configured for taking up a sample containing an analyte, wherein the sampling device comprises a sample matrix and optionally an eluent for eluting the analyte from the sample matrix； and (b) an analysis device, comprising: (i) a first region which is configured for introducing the sampling device, (ii) optionally an eluent for eluting the analyte from the sampling device, (iii) a second region which is configured for detecting the presence and/or amount of the analyte in said solution by means of surface enhanced Raman spectroscopy, and (iv) optionally a housing, wherein at least one of the sampling device and the analysis device comprises an eluent and at least one of the sampling device and the analysis device comprises SERS active particles. The analysis device may comprise a microfluidic structure. The eluent or the second region may comprise SERS-active nanoparticles. The second region may comprise a hollow-core optical fibre coated with a layer for example comprising SERS-active nanoparticles. The kit may be used for detecting an illicit drug such as cannabis, synthetic cannabinoids, ketamines, cocaine, heroin, methadone, and methamphetamines or a prescriptive drug in a body fluid sample such as sweat, saliva, urine, or blood of volume of about 100 nl to 1ml.La présente invention concerne un procédé de détermination d'un analyte à l'aide de spectroscopie de l'effet RAMAN exalté de surface et un dispositif approprié à cet effet.
